In situ synthesis of rhodium nanoparticles - Mesoporous carbon hybrid via a novel and facile nanocasting method for simultaneous determination of morphine and buprenorphine.

An in situ and facile nanocasting procedure has been developed to embed Rhodium nanoparticles (RhNPs) in mesoporous carbon (MC) matrix via carbonizing β-Cyclodextrin capped RhNPs (β-CDs@RhNPs) as a source of both carbon and metal, in the presence of SBA-15 as hard template. Firstly, β-CDs was used to coat and stabilize the RhNPs, and then coated RhNPs was applied as carbon source during the carbonization step. In this way, biocompatible materials are used as much as possible. The transmission electron microscopy, field emission scanning electron microscopy, Fourier transform infrared, BET surface area and X-ray diffraction devices were used to characterize the nanomaterials. The nanocomposite (RhNPs-MC) was casted on the glassy carbon electrode (GCE) to fabricate an electrochemical sensor (RhNPs-MC/GCE). This sensor shows high efficiency toward simultaneous determination of Morphine (Mp) and Buprenorphine (Bp), electrochemically, what other modified electrodes cannot do. For Mp, the linear range and limit of detection were obtained 0.1-20 μM and 40 nM, respectively, and these data were obtained about 0.1-14 μM and 45 nM for Bp determination. Less steps of synthesis, biocompatibility and facility are the major advantages of the process, and some benefits of the sensor are its separate signals, fast response time, sensitivity, and simple use without need for pretreatment.